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Danny becomes season’s first hurricane

11 PM UPDATE: Danny remained a hurricane with top winds of 80 mph. The updated forecast is for the storm to begin to slowly weaken starting Saturday night but maintain tropical storm strength through Tuesday night, when it is expected to be south of the Dominican Republic with winds of 50 mph. Two aircraft missions will study Danny over the next two days. The first is a NOAA research mission, set for Friday, and the second is an Air Force Reserve reconnaissance mission set for Saturday afternoon.

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5 PM UPDATE: Danny strengthened slightly to 80 mph in the latest National Hurricane Center advisory, and the storm developed an eye as it continued to move west-northwest at 10 mph. On its latest forecast path, Danny would move over the Leeward Islands in the northeastern Antilles about mid-day on Monday and arrive in Puerto Rico a day later.

Slow weakening remains in the forecast and Danny is expected to have winds of 60 mph in five days as the system encounters dry air and stronger wind shear. An Air Force Reserve Unit reconnaissance aircraft will investigate Danny Friday afternoon, which should provide more detailed data that can be used to better project intensity and track.

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ORIGINAL POST: Danny became the season’s first hurricane at 11 a.m., jumping from a 50-mph tropical storm to a 75-mph minimal hurricane in six hours.

Weakening was still forecast after Danny reaches a forecast peak strength of 85 mph.

“Danny’s compact size makes it subject to significant fluctuations in strength, both up and down, and such fluctuations are notoriously difficult to forecast,” NHC forecaster Stacy Stewart said in the late-morning advisory. “Low-shear conditions are expected to continue for the next 36 hours or so, which argues for some further strengthening during that time.

“However, the cyclone continues to be surrounded by dry mid-level air, which could penetrate into the core and disrupt the intensification process.”

Hurricane-force winds extended only 10 miles from Danny’s center, according to the NHC. Tropical storm-force winds (39-73 mph) extend 60 miles from the center.

The forecast brings Danny to Puerto Rico on Tuesday as a tropical storm.

Forecast tracks for Hurricane Danny. (Credit: SFWMD)

“Danny’s intensity forecast is more uncertain than usual because of its very small size: day-to-day conditions could produce dramatic spikes in strength, both upward and downward,” said blogger Bob Henson at Weather Underground. “Even so, the statistical and dynamical model guidance suggests that Danny is unlikely to strengthen beyond Category 1 levels over the next five days.”

How small is Hurricane Danny? Check out the tiny storm in the far right of the image, east of 50 degrees. (Credit: NOAA)

FUTURE IMPACTS: The National Weather Service in Miami says South Florida will see a “pattern change” next week that could lead to enhanced rainfall over the Florida peninsula, but mainly in the interior and West Coast. It’s too early to say what, if any, impacts Danny may have on South Florida weather next week, forecasters said.